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排序方式: 共有1451条查询结果,搜索用时 15 毫秒
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Brian J. Burke William T. Peterson Brian R. Beckman Cheryl Morgan Elizabeth A. Daly Marisa Litz 《PloS one》2013,8(1)
Most modeling and statistical approaches encourage simplicity, yet ecological processes are often complex, as they are influenced by numerous dynamic environmental and biological factors. Pacific salmon abundance has been highly variable over the last few decades and most forecasting models have proven inadequate, primarily because of a lack of understanding of the processes affecting variability in survival. Better methods and data for predicting the abundance of returning adults are therefore required to effectively manage the species. We combined 31 distinct indicators of the marine environment collected over an 11-year period into a multivariate analysis to summarize and predict adult spring Chinook salmon returns to the Columbia River in 2012. In addition to forecasts, this tool quantifies the strength of the relationship between various ecological indicators and salmon returns, allowing interpretation of ecosystem processes. The relative importance of indicators varied, but a few trends emerged. Adult returns of spring Chinook salmon were best described using indicators of bottom-up ecological processes such as composition and abundance of zooplankton and fish prey as well as measures of individual fish, such as growth and condition. Local indicators of temperature or coastal upwelling did not contribute as much as large-scale indicators of temperature variability, matching the spatial scale over which salmon spend the majority of their ocean residence. Results suggest that effective management of Pacific salmon requires multiple types of data and that no single indicator can represent the complex early-ocean ecology of salmon. 相似文献
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Yuben Moodley Vijesh Vaghjiani James Chan Svetlana Baltic Marisa Ryan Jorge Tchongue Chrishan S. Samuel Padma Murthi Ornella Parolini Ursula Manuelpillai 《PloS one》2013,8(8)
Lung diseases are a major cause of global morbidity and mortality that are treated with limited efficacy. Recently stem cell therapies have been shown to effectively treat animal models of lung disease. However, there are limitations to the translation of these cell therapies to clinical disease. Studies have shown that delayed treatment of animal models does not improve outcomes and that the models do not reflect the repeated injury that is present in most lung diseases. We tested the efficacy of amnion mesenchymal stem cells (AM-MSC), bone marrow MSC (BM-MSC) and human amniotic epithelial cells (hAEC) in C57BL/6 mice using a repeat dose bleomycin-induced model of lung injury that better reflects the repeat injury seen in lung diseases. The dual bleomycin dose led to significantly higher levels of inflammation and fibrosis in the mouse lung compared to a single bleomycin dose. Intravenously infused stem cells were present in the lung in similar numbers at days 7 and 21 post cell injection. In addition, stem cell injection resulted in a significant decrease in inflammatory cell infiltrate and a reduction in IL-1 (AM-MSC), IL-6 (AM-MSC, BM-MSC, hAEC) and TNF-α (AM-MSC). The only trophic factor tested that increased following stem cell injection was IL-1RA (AM-MSC). IL-1RA levels may be modulated by GM-CSF produced by AM-MSC. Furthermore, only AM-MSC reduced collagen deposition and increased MMP-9 activity in the lung although there was a reduction of the pro-fibrogenic cytokine TGF-β following BM-MSC, AM-MSC and hAEC treatment. Therefore, AM-MSC may be more effective in reducing injury following delayed injection in the setting of repeated lung injury. 相似文献
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Wei Shen Tan Pramit Khetrapal Wei Phin Tan Simon Rodney Marisa Chau John D. Kelly 《PloS one》2016,11(11)
BackgroundThe number of robotic assisted radical cystectomy (RARC) procedures is increasing despite the lack of Level I evidence showing any advantages over open radical cystectomy (ORC). However, several systematic reviews with meta-analyses including non-randomised studies, suggest an overall benefit for RARC compared to ORC. We performed a systematic review with meta-analysis of randomised controlled trials (RCTs) to evaluate the perioperative morbidity and efficacy of RARC compared to ORC in patients with bladder cancer.MethodsLiterature searches of Medline/Pubmed, Embase, Web of Science and clinicaltrials.gov databases up to 10th March 2016 were performed. The inclusion criteria for eligible studies were RCTs which compared perioperative outcomes of ORC and RARC for bladder cancer. Primary objective was perioperative and histopathological outcomes of RARC versus ORC while the secondary objective was quality of life assessment (QoL), oncological outcomes and cost analysis.ResultsFour RCTs (from 5 articles) met the inclusion criteria, with a total of 239 patients all with extracorporeal urinary diversion. Patient demographics and clinical characteristics of RARC and ORC patients were evenly matched. There was no significant difference between groups in perioperative morbidity, length of stay, positive surgical margin, lymph node yield and positive lymph node status. RARC group had significantly lower estimated blood loss (p<0.001) and wound complications (p = 0.03) but required significantly longer operating time (p<0.001). QoL was not measured uniformly across trials and cost analysis was reported in one RCTs. A test for heterogeneity did highlight differences across operating time of trials suggesting that surgeon experience may influence outcomes.ConclusionsThis study does not provide evidence to support a benefit for RARC compared to ORC. These results may not have inference for RARC with intracorporeal urinary diversion. Well-designed trials with appropriate endpoints conducted by equally experienced ORC and RARC surgeons will be needed to address this. 相似文献
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